Tamperproof slide lock for doors



June 1969 c. D. ROEGNER TAMPERPROOF SLIDE LOCK FOR DOORS Filed July 7.1967 INVENTOR. Char/es l7. Foggy 21; WM v Affa/wQ/s' United StatesPatent US. Cl. 292-148 2 Claims ABSTRACT OF THE DISCLOSURE A tamperproofslide lock for doors and the like having a base plate secured to thedoor by fasteners such as screws. The bolt is carried by a slide plateand the bolt passes through at least one lug, carried by the base platewhereby the base plate and slide plate are captive and the bolt may bemoved from locked to unlocked position by sliding the slide platerelative to the base plate. The slide plate isprovided with openingswhich provide access to the fasteners only when the parts are in anintermediate position, between. locked and unlocked position. Openingsin the slide plate and. base plate permit a padlock or the like tosecure the device either in locked or unlocked position, thus preventingthe removal of the fasteners in either position.

My invention relates to tamperproof slide locks for doors and the likeand has for an object the provision of such a device which may besecured in either locked or unlocked position by means of a padlockwhereby the fasteners securing the base plate to the door areinaccessible.

Another object of my invention is to provide a device of the characterdesignated in which the base plate and slide plate are captive relativeto each other, preferably by providing a pair of lugs on the base platethrough which the bolt slides and further to provide, between the lugs,an enlargement on the bolt, thus completing the captive assembly of theparts.

A further object of my invention is to provide a device of the characterdesignated which the base and slide plates may be of angle shape incross section, the out- 'standing leg of the base plate being providedwith a single opening and the outstanding leg of the slide plate beingprovided with two openings, the openings being so relatively arrangedthat the hasp of a padlock or the like may be passed through theopenings, selectively, thus to lock the device either with the boltextended or with the bolt withdrawn, thereby preventing the movement ofthe parts to the intermediate, fastener exposing position.

In the art to which this invention relates a considerable amount ofdifliculty has ben experienced by warehouse and store owners withdishonest employees who, while working in normal. store hours willremove the fasteners from locks and the like, generally at a back orside door. After store hours such employees are therefore able to openthe tear or side door of the establishment and make away withmerchandise therein.

My invention contemplates a slide lock, the base plate of which is heldto the door by fasteners and the slide of which may be locked in suchposition as always to cover the fasteners, whether the bolt is in doorlocking or door unlocking position. Thus, in compliance with the usualfire laws, the rear or side doors, during store hours, must be unlockedand yet, with my invention, with the padlock or other locking device inplace on my improved slide lock, the securing fasteners for the baseplate are inaccessible even though the door itself is unlocked. Further,when it is desired to lock the door after store hours the slide lock ismoved to door locking position and the padlock inserted and thefasteners still are inaccessible.

3,451,703 Patented June 24, 1969 I 2 Further, my invention contemplatesmaking captive the slide and lock plates and to provide an automaticstop means for holding the parts assembled which also properly align theholes for the padlock in the respective base and slide plates.

Apparatus illustrating features of my invention is shown in theaccompanying drawings forming a part of this application, in which:

FIG. 1 is a view of the apparatus showing the same mounted on the freeedge of a door and with the bolt thereof in engagement with a keepermounted adjacent the opening in which the door moves;

FIG. 2 is a side elevational view of the same in the position shown inFIG. 1 but with the keeper and padlock removed;

FIG. 3 is a front elevational view showing the parts in the intermediateposition, that is, a position between locked and unlocked relationthereby to expose the fasteners which hold the base plate to the door;

FIG. 4 is a view corresponding to FIG. 1 with keeper omitted and showingthe slide bolt assembly padlocked in door unlocking position;

FIG. 5 is a side elevational view of the apparatus in the position shownin FIG. 4; and,

FIG. 6 is an end elevational view of the device shown in FIG. 3.

Referring now to the drawings for a better understanding of my inventionI show the same as being mounted upon the side of a door at the endthereof, a fragment of which is indicated at 10. As the descriptionproceeds it will be apparent that my invention may be applied to hinged,sliding and folding doors, and other types of closures.

As best shown in FIGS. 1 and 4, the base plate 11 is secured with itslonger leg 11a flush with the side of the door and is held in place bymeans of a plurality of fasteners 14 which may be wood screws. Thedevice thus is mounted adjacent the free end of the door and in positionfor the end 16 of the bolt 13 to project into a keeper 17 mounted in astationary part of the opening in which the door is hung.

The base plate is provided with a pair of spaced apart lugs 18 and 19having aligned openings therein through which the bolt 13 is slideablyreceived. An enlargement 21 which may be in the form of a washer or thelike is secured to the bolt 13 between the lugs 18 and 19. As willappear this enlargement acts to hold the slide plate, 12 captiverelative to the base and also serves to align certain openings in thelegs of the slide plate 12 and base plate.

The slide plate 12 is provided with an outstanding leg or projection 22which slides alongside a similar projection 23 on the base plate 11. Theleg 23 is provided with a single opening therethrough indicated at 24and which is located adjacent the end of the assembly opposite the bolt.The leg 22 of the slide plate is provided with a pair of spaced openings26 and 29 which, when the slide is moved relative to the base may beselectively aligned with the opening 24. Therefore, with the parts inthe position of FIG. 1 and the opening 26 aligned with opening 24, thehasp 27 of a padlock 28 may be inserted through the openings thus tolock the slide and base plate with the bolt extended. A third opening 29is provided in the leg 22 of the slide plate. With the parts in theposition of FIG. 4 the openings 29 and 24 are aligned whereby thepadlock may be inserted to lock the parts with the bolt withdrawn.

It will be noted that the leg 31 of the slide plate is provided with aplurality of openings 32. These openings are so disposed longitudinallyof the slide plate and laterally thereof that when the parts are in theposition of FIG. 3 the openings 32 uncover the screws 14. In this mannerthe screws may be inserted or removed. However, and as stated, when thedevice is secured by means of the padlock in either bolt latched orunlatched position, all the fasteners except the uppermost one 14 asshown in FIG. 4 are covered and hence are inaccessible.

It further will be noted that the enlargement on washer 21 is sorelatively spaced that when the bolt is pushed outwardly the washerstrikes against the side of lug 18, thus to bring the openings 24 and 26into alignment. When in the position of FIG. 4 enlargement 21 strikesthe side of lug 19 thus to bring openings 24 and 29 into alignment.

It will be apparent that instead of using angle shaped members the partsmay be built with projections corresponding to the legs 22 and 23, thesebeing long enough, of course, to afford the positioning of the openingsin the legs 22 and 23.

In view of the foregoing it will be apparent that I have devised animproved tamperproof bolt type slide lock. In use, during the daytime ornormal store hours, the manager of the store locks the device in theposition in FIG. 4 whereupon the door may be opened as required by thefire code. In this position it is impossible for dishonest employees orothers to remove the fasteners, At night, or when the store is closed,the parts are locked in the position of FIG. 1, similarly covering andmaking inaccessible the fasteners. It will also be noted that by cuttingan L-shaped portion away from the top of the slide as indicated at 33the upper leg 31 of the slide plate may lie directly on the uppersurface of the longer leg of the base plate 11, whereby the lugs 18 and19 afiord some degree of protection against knocking the slide plate offthe base plate. However, it would be practical to secure the bolt bywelding or otherwise to the leg 31 and cut the leg off all the wayacross along the line 34. This would eliminate some of the upperfasteners, but in some circumstances such an arrangement would besatisfactory.

In view of the foregoing it will be apparent that I have devised animproved slide type of lock which is tamperproof. In use I have foundthe device to be practical, simple of operation and reliable.

While I have shown my invention in but one form, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various other changes and modifications without departing from thespirit thereof.

What I claim is:

1. In a tamperproof slide lock for doors mounted in openings,

(a) a base plate adapted to be secured to the door adj acent the freeend thereof, (b) a plurality of spaced apart fasteners passing throughthe base plate and into the door for securing the base plate to thedoor,

(c) a slide plate,

(d) a bolt carried by the slide plate and disposed in extended lockedposition to engage a keeper mounted adjacent the door opening and inwithdrawn position to permit the door to move relative to the open- (e)an outstanding lug on the base plate slideably receiving the bolt, (f)means to secure the slide plate against movement relative to the baseplate both in bolt extended, locked position and bolt withdrawn,unlocked position, and (g) openings through the slide plate spaced aparton centers corresponding with the spacing of said fasteners andalignable with said fasteners only when the slide plate is in anintermediate position between said locked and unlocked positions, therelative disposition of said fasteners and openings when the slide plateis secured in both the locked and unlocked positions being such thatsaid fasteners are inaccessible. 2. Apparatus as defined in claim 1 inwhich the base plate and slide plate are provided with outwardly turnedprojections slideable alongside each other, said means to secure theslide plate against movement relative to the base comprising openingsthrough the outturned projections on the slide plate and base plate,certain of said openings coming into alignment when the parts are inlocked position and others thereof coming into alignment when the partsare in unlocked position, whereby a securing member may be passedthrough the openings thereby to secure the parts against relativesliding movement selectively in locked or unlocked position.

References Cited UNITED STATES PATENTS 2,198,079 4/1940 Ferris et al.292143 2,468,406 4/1949 Mora -129 2,482,341 9/1949 Holmsten 292----148.2,974,987 3/1961 OBrien 292-148 3,334,933 8/1967 Ehlers 292148 FOREIGNPATENTS 853,639 12/1939 France. RICHARD E. MOORE, Primary Examiner.

R. L. WOLFE, Assistant Examiner.

U.S. Cl. 70-129

